Automatic balance



May 17, 1932.

Original Filed Aug. 9, 1930 3 Sheets-Sheet l y 17, 1932- G. RAASCHE1,859,059

AUTOMATI C BALANC E Original Filed Aug. 9, 1930 3 Sheets-Sheet 2 Fig.3

J lnventap: M ma, M WW,

May 17, 1932. G. RAASCHE 1,859,059

AUTOMATIC BALANCE Original Filed Aug. 9, 1930 3 Sheets-Sheet 3 [71 ranfor:

Her/Yard fiaasc/re Patented May 17, 1932 v UNITED STATES PATENT OFFICEGERHARD RAASGHE, F RIGA, LATVIA, ASSIGNOR TO THE FIRM PAUL RAASCHES6HNE, OF'RIGA, LATVIA, A LATVIAN COMPANY AUTOMATIC BALANCE qriginalapplication filed August 9, 1930, Serial No. 474,252, and in LatviaAugust 15, 1929. Divided and this application. filed October 8, 1931.

The present invention relates to the arrangement and connection of thelevers in an automatic balance to insure uniform arcuate notion of thedeflection indicator to an hitherto unattained extent. The uniformarc-like motion of the deflection indicator is effected by transmittingthe irregular arcuate motion of the inclinatory lever toa lever arm ofthe inclinationindicator by means of an ordinary draw bar, the lever armmaintaining a certain ratio to the length of the inclinatory lever so asto bring about the uniform arcuate motion of the deflection indicator.Steel bands which break easily and cause much friction as well assegments which are difficult to produce and require greatest accuracy,means hitherto employed for effecting the uniform arcuate motion of thedeflection in dicator, can thus be dispensed with.

By way of example, one form of an automatic balance according to theinvention is illustrated in the accompanying drawings, in which Figures1 and 2 are vertical sections of the balance;

Fig. 3 is a horizontal section thereof;

Fig. 4: is a view on an enlarged scale of the 'connection'of theinclinatory lever with the deflection indicator and also with theplatform levers;

Figs. 5 and 6 are enlarged fragmentary side elevations of connections ofthe inclinatory lever with the deflection indicator and also theplatform levers Figs. 7 and 8 are fragmentary and enlarged detail viewsof the means for adjustably conn'ecting the draw bar and lever arm; and

I Fig. 9 is an enlarged view of the scale of the indicating device forthe small units. 1" Referring to the drawings, the inclinatory 'lever lrests with its edge-like axis 2 on seats of the standard 3 and carriestwo edges 4: and 5 to-which the load ofthe platform 6 is transmitted bymeans of thelevers 7 and 8 and the draw bars 9 and 10. To theinclinatory lever 1 the pendulum rod 11 with the adjustable weight'12 isremovably attached in order to adjust the lever without the pendulumrod.

Furthermore, an edge 13 is provided to be en- Serial No. 567,725.

gaged by the draw bar 14 connecting the inclinatory lever with the leverarm 16 of the deflection indicator 17 the bar 14; transmitting themotion of the inclinatory lever 1, by means of the lever arm 16, to thedeflection indicator 17 swinging about the axis 18 and verticallybalanced by the counterweight 19. The draw bar 14 carries the pot whichmay be filled with lead as required to compensate the tare. The top endof the indicator 17 carries an indicating device consisting, forexample, of a scale plate 20 over which a small pointer 21 circulates toindicate the small units of weight, the pointer being moved by a gear 22rotating over the toothed segment 23, see Figure 9, and which is thesubject matter of a separate recent U. S. patent to me, No. 1,857,870,dated May 10, 1932. To transform the uneven arcuate motion of theinclinatory lever 1 into a uniform arc-like motion of the deflectionindicator 17, it is necessary to bring the lever arm 16 into a definiterelation to the lever arm of the inclinatory lever 1. The followingapproximate formula will be found useful in calculating the lengths ofthe levers ,8 indicates the full deflection of the member 17 in degrees;1, the length of the lever arm 16 of the member 17; and r the length ofthe lever arm of the inclinatory lever 1. The compensation ispractically complete, the difference at a deflection of of the indicator17 being only 1 50,000, while, on the average, balances are consideredto be good if they show an accuracy of 1 1,000. The calculation ofleverage according to this formula must be based of course on maximumdeflection. This method of compensation affords the advantage that thedeflection indicator 17 describes a much greater angle than theinclinatory lever 1 (a5:26); furthermore, power can be transmitted toedges by means of long draw bars, and, owing to the high position of theinclinatory lever 1, the pendulum rod 11 may belong and the weight 12small, while the tare'can be compensated conveniently by the lead-filledpot 15, whereby the bar 14% will be firmly disposed again on the edge13,

toothed segmentw23 should idisclose: some. inaecuracies. The lengthof-.thelever' arm-.163, see.

Figures 4, 7 and 8, is adjustable by a pin 4-2 which can be insertedinto one of several-holes 43 in saidlarm 16 and registering hole 44 in.

the bar 14, as shown.

The deflection of the inclinatory lever l'is limited by; the set screws2.5 ancLthe impact softenedkby. a aubber buffer 26v on the pendulum rod411; Moreover-,'the. movements ofthe bridge 6 are softened by a brake27. In case of ordinary table and fioorbalances the. small taredifference and zero errors-produced by wantoilevel in the. support forthe scale are eliminated by the-.setscrews 28, while in largerb'alancesinvolving greater tare differences the curvediscale 24gwith thetoothedsegmentflii isadjusted from withoutby. means of set screws,the-fulcrum: of which coincides of course ,with the'axis 18of;thedeflection in: dioator. 17

Thisharmonizing of the lever lengths-relativeto. one another totransform the irregular arouatemotion of the inclinatorylever; 1 intoa-Jlniform motiomof the deflection indicator 17. canv he carried out.without any. trouble, asthe levers ofthe balance, on. which theplatfornrrests, lead in the-same direction directly tozthe draw barsestablishing connection withtheginolinartory,lever. In balances of theknown type this. was hitherto impossible. for the reasontliat= usuallyonly one lever leads to the inclinatory lever and the other one isplacedainopposite direction on the first one meansof suspension, so thatthe two. levers. always describe. opposite arcs.

. Itwas. necessary to. suspend the platform or the. levers to preventtheplatform from :sliding on theedges during. the ascent and descentofJtheJevers. This arrangementcan be.v dispulsed 'with v in the balanceaccording to the invention, since the. platform rests on the bridgelevers equidistantly from the. axesofthe.-.levers, the leversextendlinthe same di-v rection. and. thus.- describe. the same. arcs.Therefore, duringthe descent offthe levers uniformtran-smission ofweighttakes place,

andthere will beno distortions as in balances employing leversvextendingin opposite. directions.

Transmission of the. platform loadv to the incli'natory. lever 1.is.effected, .as stated,,bv

means. of the platform levers? .and .8 and the draw bars 9, and 1O.The-levers 7 and18 exv tend {in the same direction and are firmly con-1nectedfwiththeir. edge-like axes :29. and 30. which: rest onthe ,cupbearings. .31 Connection between the levers 7 and 8 and the draw bars 9and 10 is effected by means of the edges 32 and 33. The edge-like axes29 and 30 carry further the shoes 38 and 39. The platform 6.. thus.rests onfour. points on the variousrzlevers, i. e., onpthe two.edges+34 of the lever 7 and the shoe 38 and on the two edges 35 of thelever 8 and the shoe 39. The edges Hand Softheinclinatorydtevw: bysthedrawbars 9Im1d l0 are spaced relative to the axis 2 of the inclinatorylever in the same proportion which determines the relative length oftheplatform levers 7 and 8, but the ed es34 and 35' areabsolutelyequidistant from the axes 29and'30. The edges 34 and 35 thusdescribethesame arc-likemotionin the same direction at-theascentranddescentni thelevers7 and 8 and the .ShOfiS-38t8l1di and: theplatform 6,.the. carriers 36. M14137 0 which are provided with seats,1.canrestfldii reotly on the edges 34..a.ndv 3.5 without. 001m pensatingsuspension as-required iin-the ing types-ofbalanceshaving-oppositelyJmvr ing levers inzorder. to preventzthe Seatsimmsl-idingon the edgesiaiidthe balance from failinggto weigh.

Of course, shoes.-like38 and:39 mybeeq '1 distantly positioned from the.center other sidesof the levers7 311C118 .alseandtha latter-be movedmoretowards' the ceatm which is preferable in large balancea. For thesmallestv type of. automatic. balancesthe platform levers 7 and '8 maybeprovided with two arms:

1. utomatie: balance-com rism' ga sap rately disHosed deflectionindicator. pointiig out the large units of weight on an qipidiie ta-ntlydivided arcuate, scale, an .inclinatory lever, a lever arm for the saiddeflectionim dicator, and a. draw bar.- conneeting thmslid mclinatory.lever. with thesaidlevan arm; .the relative length of. the. said leverarm; ancliin: clinatory lever beingproportioued. accord: ing to theformula insuring uniform arcuate motion ofjtlie Said inclinatory lever,i3 indicating the: full; deflection ofith'e deflection indicator in .d'ees; r, the length of the lever arm ofth'e tion indicator; and 73., thelength of the lever arm, of the inclinatory lever.

2." Automatic balance comprising a-sepa: rately disposed deflectionindicatorv carrying out'a uniform arc-like motion and pointingdirection, draw bars transmitting the motion of the other ends of thesaid platform levers to the said inclinatory lever and. enga ing thesaid inclinatory lever according to tie ratio of length of the platformlevers at pivot distances, shoes firmly connected with the axes of thesaid platform levers and parallel to the latter, and a platformsupported equidistantly from the axes of the said platform levers atfour points by the said levers and shoes.

In testimony whereof I have aflixed my signature.

GERHARD RAASCHE.

